Open AccessOn the NO 2 + soot reaction in the atmosphere
Author(s) -
Aumont B.,
Madronich S.,
Ammann M.,
Kalberer M.,
Baltensperger U.,
Hauglustaine D.,
Brocheton F.
Publication year - 1999
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1998jd100023
Subject(s) - soot , troposphere , atmospheric chemistry , nox , atmospheric sciences , atmosphere (unit) , environmental science , ozone , chemistry , meteorology , environmental chemistry , combustion , geology , physics , organic chemistry
Recent modeling studies have suggested that soot is a key component of tropospheric chemistry in remote regions, acting to reduce HNO 3 to NO 2 and possibly NO 2 to NO. It may be expected then that soot also affects the chemistry of rural and urban areas, where soot concentrations are typically several orders of magnitude higher than in the remote troposphere. In order to test this assumption, a modeling study was conducted for typical urban and rural areas, with the same HNO 3 /NO 2 /soot chemistry proposed in the previous modeling studies of the remote troposphere. Unreasonable results were found (e.g., nearly total suppression of urban ozone, in contradiction to common observations), suggesting that the NO 2 /soot reaction was considerably overestimated in previous modeling studies. Therefore the NO 2 /soot chemistry was reconsidered. A new preliminary mechanism is suggested, based on recent laboratory studies of this reaction. Results show that the NO 2 /soot reaction does not notably affect the Ox‐NOx‐HOx chemistry of the lower continental troposphere, except maybe during nighttime in urban environments. A potential contribution of the NO 2 /soot interaction to HONO production is noted.